1. Field of the Invention
The present invention relates to an eye optical characteristic measuring apparatus for measuring eye optical characteristics.
2. Description of the Related Art
Since a Hartman-Shack wavefront sensor can accurately measure wavefront aberrations of an eye, it has recently attracted considerable attention. This wavefront sensor can become a necessary apparatus in eye surgery in near future especially for the purpose of the planning and follow-up of cornea refractive surgery.
The measurement of the eye wavefront aberrations by the wavefront sensor is greatly different from the measurement of corneal wavefront aberrations by corneal shape measurement in that the measurement result includes an influence of an intraocular optical system, such as a crystalline lens, on the wavefront aberrations. According to this function, it becomes possible to perform an examination in a case where the crystalline lens has refractive index abnormality due to nuclear cataract or the like or in a case where the shape of a refractive plane of the crystalline lens is largely distorted by lenticonus.
As an object of the eye optical system wave front aberrations measurement, an objective evaluation of visual functions can be named. As the evaluation of the visual functions, a subjective examination has been conventionally recognized as a reliable measurement method as compared with an objective examination. Especially, this is true to such an extent that with respect to an auto-refractometer as a former wavefront sensor, a lens interchange method as the subjective examination is called a gold standard.
When the eye wavefront aberrations measured by the wavefront sensor is compared with corrected eyesight or contrast sensitivity, there is a case where they are fully coincident to each other, and there is a case where they are not coincident to each other especially in, for example, old people. In the case of the inconsistency, there is a case where scattering has a large effect on the eyesight.